Session Nodes don't work

Hi, I got a problem with the session nodes again… this time, create session simply does not work, it also fires the “fail” event. I configurated the DefaultEngine.ini (

[OnlineSubsystem]
DefaultPlatformService=LAN

also tried …=Null, did not help)
I have no idea what else could cause a failure of the session nodes, did you guys make any experience there?
Thanks in advance

I have just got back into UE4 - I’ve loaded up a clean project with 4.8.2 and set the Online Subsystem to Null as I did before for local testing. When I use the Create session node it always fails.

that’s really strange it seems like completely random if it works or not…